Fuse construction



3 1941- A. G. STEINMAYER 2,251,471

FUSE CONSTRUCT ION Filed May 2, 1938 5 SheetsSheet 1 J c/ INVENTOR. I401 076: IJTE/A/MAVEAD- BY 1 4 3:1 flWW EY.

Aug 1941' A. e. STEINMAYER FUSE CONSTRUCTION 5 Sheets-Sheet 2 Filed May2, 1938 INVENTOR. 4114M 6T Jaw/WAVE? ATTORNEY.

Aug 5, 1941- A. G; STEINMAYER FUSE CONSTRUCTION Filed May 2, 1938 5SheetsSheet 3 IIIIIIIIII SSR I" INVENTOR. /4m///v 6. 570mm Yffi 4:2; 444 TWK ATTORNEY.

- Aug 5, 1941.

A. G. STEINMAYER FUSE CONSTRUCTION Filed May 2, 1938 5 Sheets-Sheet 4Aug 1941- A. G. STEINMAYER 2,251,471

FUSE CONSTRUCTION Filed May 2, 1938 5 Sheets-Sheet 5 INVENTOR. 41M 6?Jrfl/vM/Wm v ATTORNEY.

Patented Aug. 5, 1941 FUSE CGNSTRUCTIQN Alwin G. Steinniayer, Milwaukee,Wis assignor to Line Material Company, South Milwaukee, Wis, acorporation of Delaware Application May 2, 1938, Serial No. MEL 87 (Cl.zoo-117) 18 Claims.

This invention relates to a fuse construction.

Objects of this invention are to provide a simple fuse constructionwhich may be used in any capacity but which is eminently suitable as afuse construction for association with a transformer or other electricaldevice.

This invention is intended to provide a fuse construction which isparticularly useful on a single bushing transformer as thesetransformers have come into quite general use for rural service. Thesetransformers are provided with only one primary bushing, the other sideof the primary winding being solidly grounded to the transformer case.

Objects of this invention are to provide a fuse construction which iscarried or supported from the transformer casing, which is so arrangedthat the discharged gases are directed away from the casing and do notcontact with the casing, in which such discharged gases are so directedthat they do not endanger a lineman even when he is refusing thetransformer and the overload still exists, and which is so made that thefuse may swing in a horizontal plane above the top of the transformercasing.

Further objects are to provide a fuse construction in which thetransform er bushing is not sub jected to the stresses due to supportingand mounting the fuse tube, in which the fuse is so made that it may bereadily removed during refusing without danger to the lineman, in whichmeans are provided for mechanically assisting in with-drawing anyunburned portion of the fuse link or leader, in which any remainingunburned portion of the fuse leader is kept away from the live terminal,and in which the invention in one form may provide means formechanically releasing the extracted remaining unburned portion of thefuse link so that it may be dropped or thrown from the device.

Further objects are to provide a fuse construction for a single bushingtransformer in which surge protection is afforded by means of a sparkwhich is so connected that after the fuse blows, the transformer isseparated from the line but any surges that may occur are taken care ofby the spark gap.

Further objects are to provide a construction such that when the fuseblows, a clear indication is given so that the lineman may readilyascertain whether the fuse is intact or whether it needs refusing.

Embodiments of the invention are shown in the accompanying drawings, inwhich:

Figure l is a top view of a transformer equipped with one form of theinvention.

Figure 2 is a side elevation of the structure shown in Figure 1.

Figure 3 is an enlarged fragmentary view corresponding to Figure 1 withparts in section.

Figure l is a view corresponding to Figure 3 showing a modified form ofthe invention.

Figures 5, 6 and 7 are views of further modified forms.

Referring to Figures 1, 2 and 3, it will be seen that a transformercasing has been indicated by the reference character I and is providedwith a top or cover 2. The casing and cover are usually made of metal,though obviously other materials could be used provided a groundconnection were furnished for the lower member of the spark gaphereinafter described.

The transformer is provided with a bushing 3 which carries the upperterminal 4 for the primary. A line receiving terminal 5 is also carriedby an insulator 6. One side of the primary, not shown, is connected tothe terminal 4 and the other side is grounded within the casing in theusual manner for a single bushing transformer.

The terminal 5 is provided with a connecting portion '5 projectingupwardly therefrom to which the line wire, not shown, may be connectedin any suitable manner as by means of the connector B. The terminal 5 isalso provided with an outwardly projecting arm 9 which carries anadjustable upper electrode IE! forming one portion of the spark gap, thelower electrode H of which is carried by the cover 2 of the transformer.

The fuse comprises an insulating tube l2, one end of which is screwedinto a body portion or fuse terminal member l3 which has an aperturetherethrough closed by a screw cap it in the usual manner and clampingthe button of the fuse link E5 in the usual manner. The fuse tubeterminal 13 is secured to the line terminal 5 in any suitable manner.For example, it may be provided with the clamping member consisting of arigid, substantially U-shaped portion i5 integral with. the member [3and receiving the screw H, such screw having a manipulating eyelet it atthe outer end and having a notched head is) at its inner end to clamprigidly against the upstanding portion 1 of the terminal 5 so as toallow the ready removal of the fuse tube therefrom. The construction ofthe clamping member is very similar to a hot line clamp, though otherforms may be used provided they removably support the fuse tube from theline terminal 5.

The terminal 4 of the transformer carries an outwardly projecting arm 29which is provided with a recess 2| flaring towards the outer end. At itsouter end it is provided with a laterally offset portion 22 which isprovided with a pivot pin 23. A rocking arm or fuse extracting andclamping arm 24 is provided with a slot 25 formed in an inwardlyprojecting lug thereof and receiving the pivot pin 23.

A spring 26 extends between the outwardly projecting portion of thelever 24 and the member 20 and is housed within the recess 2|. Themember 241 is provided with a thumb manipulating ear or foot 21 at itsouter end and with a channel terminal portion 28 at its inner endadjacent the fuse tube l2 and adapted to receive within such channelportion the leader of the fuse link 15. The fuse link clamping andextracting lever 24 is provided with a boss or projecting portion 29,and the member 20 is provided with a similar projecting portion 30between which the leader of the fuse link is clamped. Preferably theseprojecting bosses 2S and 30 are staggered or set one in front of theother, as shown most clearly in Figure 3.

When the fuse blows, the gases and metallic vapors are projected in ahorizontal plane outwardly away from the transformer casing. As soon asthe fuse link is ruptured, it is expelled by the generated gases butalso it is mechanically quickly withdrawn by means of the spring urgedlever 24. It is to be noted that as the lever 24 rocks in acounterclockwise direction, as viewed in Figure 3, that the outward pullof the lever is at first substantially in line with the fuse tube andconsequently very little flexing of the leader of the fuse link isrequired. Thus a stiffer leader could be used if desired. Also duringthe first portion of the stroke of the lever 24, the fuse link is stillgripped between the bosses 29 and 30, but as the lever 24 continues itsrocking motion, the fuse link is freed and is thrown or dropped from thedevice.

This mechanical withdrawing of any unburned portion of the fuse linkmaterially assists in the quick extinguishing of the are within the fusetube.

It is intended that means, not shown, be provided whereby the terminal 5may be disconnected from the high tension line. For example, inaccordance with a very common practice, the connecting wire from theterminal 5 may be provided with a hot line clamp of well knownconstruction and not shown on the drawings, so that it may be detachedfrom the line prior to refusing of the device. The fuse tube is removedfrom the terminal 5 by releasing the clamping screw H, see Figure 3, andis refused. Thereafter it is replaced and the screw tightened. Theoperator then presses the fot or ear 2'! of the lever 24 outwardly withhis thumb and inserts the leader of the fuse link betwen the bosses 29and Si].

In the form of the invention shown in Figure 4, the transformer terminalis indicated at 3| and the line terminal at 32. An arm 33 correspondingto the arm 39 extends outwardly and carries the adjustable upperelectrode 34 corresponding to the electrode ll! of the spark gap, of thefirst form of the invention.

This construction may be provided with an upstanding portion 35 to whichthe line wire, not shown, may be connected. It is also provided with alaterally projecting lug 36 to which is and 33 located on opposite sidesof the bar. The bar 31 is provided with a recessed portion 48 whichreceives the pivot pin 4! carried between a pair of lugs 42 integralwith the end or terminal 43 of the fuse tube 44. The spring 38 extendsoutwardly beyond the portion 4t of the bar 3'! and is provided with anoutwardly turned outer bolted a relatively rigid bar 31 and springs 38end 45. It is to be noted that the bar 3'! terminates in an outwardlyturned end 45. The spring 39 is spaced outwardly from the bar 37 for themajority of its length and has a flat portion bearing against the button4? of the fuse link 48 and thereby connecting the terminal 32 directlywith the fuse link.

The transformer terminal 3| carries a clamping bracket 49 which isprovided with an outwardly projecting threaded pin 56 receiving theclamping nut 5| by means of which the leader from the fuse link 48 isclamped.

It is to be noted that the pivot pin 4% of the fuse tube is offset withrespect to the point at which the spring 39 exerts its pressure.Consequently there is a tendency of the fuse tube to pivot about thepivot pin 4| in a clockwise direction, and when the fuse link isruptured, the tube is quickly moved in a clockwise direction, thuswithdrawing any remaining unburned portion of the fuse link and actuallymechanically moving the end of the fuse tube to a greater distance awayfrom the terminal 3| of the transformer.

It is intended that means, not shown, be provided whereby the terminal35 may he disconnected from the high tension line. A connecting wirefrom the terminal 35 may be provided with a hot line clamp, a wel knownconstruction and not shown in the drawings, so that the connecting wiremay be detached from the line prior to refusing of the device. The fusetube may be then grasped by the operator and removed from the pivotsupport 43 of the bar 31, for when the pivot pin 4| is pulled directlyoutwardly, the spring 38 will yield sufficiently to allow the pivot pinto pass. Thereafter a new fuse link is placed in the fuse tube and thetube repositioned by passing the pin 4| between the spring 38 and theout-turned portion 48 of the bar 31, the spring again yielding andallowing the pin to go into place. The end of the fuse may then beclamped by the thumb nut 5| and the hot line clamp repositioned.Obviously if desired the device could be refused without removing thedevice from the pivot support 40.

It is apparent that a closed end fuse tube could be employed with therest of the structure shown in Figure 4. For example, the end d3 of thefuse tube could be provided with a screw cap. as in Figure 3 forinstance, and the spring 38 could engage this screw cap.

In the form of the invention shown in Figure 5 the transformer bushingis indicated at 52 and the terminal portion from the transformer isprovided with a terminal arm 53 that projects laterally outwardly andupwardly. A second insulator 54 is provided above the bushing 52 andcarries the terminal 55 which is connected to the line. The transformerterminal arm 53 may be provided with the link clamping and throwoutmechanism similar to that shown in Figure 3, and as in Figure 3,including the movable spring urged member 24 provided with the ears 28and pivotally supported in the stationary portion 'Z-J'. The stationaryportion 29' may be integral or may be attached to the arm 53 as desired.The fuse tube I2 may be provided with the clamping members l5 and i9, asin Figure 3. The device shown in Figure 5 may be refused in exactly thesame manner as that described in connection With Figure 3.

It is obvious that the parts may be reversed from that shown in Figure5. This reversal of parts is shown in Fig re '7. In this figure, thetransformer bushing is indicated at 52 and the upper insulator at 54. Anoutwardly and up wardly projecting arm 51 is secured to the transformerterminal 58 and the upper end of the arm 5'! is provided with a pin 59to which the fuse is removably clamped, as previously described, bymeans of the clamping portions 60 and 5!, the fuse tube being indicatedby the reference character 62. The fuse link extracting and throw-outmechanism is supported from the upper end of the insulator 54 and isconnected to the line Wire by any suitable means, as by means of theconnector $3. The throw-out mechanism has its stationary portionindicated at 54 and the spring urged movable portion at 65, the earsbetween which the fuse link passes being indicated at 5%. The deviceshown in Figure 7 may be refused in exactly the same manner as thatdescribed in connection with Figure 3.

It is obvious that the form of the invention shown in Figure 4 could beapplied in the same general manner as that illustrated in Figure 5. Thishas been shown in Figure 6.

The arm 53 corresponding to the arm 53 of Figure 5 is provided with athumb nut 51 which clamps the leader 58 of the fuse link extending fromthe tube Ml. This tube may be mounted in the same manner as in Figure l.The terurinal member is provided with a connector 5i which receives theconductor from the line wire. As described connection with Figure 4, itis preferable to provide a hot line clamp for the connecting wire fromthe terminal 55 so that the device may be refused in the mannerdescribed for Figure 4. The terminal 55 is supported from an insulator54 which corresponds to the insulator 5d of Figure 5.

It will be seen that in all forms of the invention mechanical means areprovided for increas ing the separation of different parts of thecircuit, in addition to the rupturing of the fuse link, so that there isno chance of carbonizing or burning the fuse tube after the fuse linkhas been It will be seen further that the device is very simple, thatthe discharge of gases is in a horizontal plane above the top of thetransformer casing and consequently during refusing if the fuse blows,the projected incandescent gases and metallic vapors are not adjacentthe lineman and greater protection is thereby afforded the lineman ifthe overload continues during refusing.

It is to be noted further that the position of the parts, either of thelever 24 of Figure 3 or 2d of Figure 5 or of the fuse tube 44 of Figure4 or M of Figure 6, will give a clear indication of a blown fuse and maybe readily detected by a lineman.

Although this invention. has been described in considerable detail, itis to be understood that such description is intended as illustrativerather than limiting, as the invention may be variously embodied and isto be interpreted as claimed.

I claim:

1. A fuse construction comprising a support, 75

a fuse unit mounted horizontally above said support in a plane spacedfrom said support, a pair of terminals normally electrically connectedby said fuse unit and supported from said support, said fuse unitincluding a stationary fuse tube, and a fuse link in said fuse tube, oneof said terminals having fuse link extracting means electricallyconnected to said fuse link and biased towards fuse link extractingmotion.

2. A fuse construction comprising a support, fuse unit mounted in asubstantially horizontal plane spaced from said support, a pair ofterminals normally electrically connected by said fuse unit andsupported from said support, said fuse unit including a stationary fusetube, and a fuse link in said fuse tube, one of said terminals havingfuse link gripping and extracting means normally gripping said fuse linkand yieldingly urged towards fuse link extracting position.

3. A fuse construction comprising a support, a fuse unit mounted in asubstantially horizontal plane spaced from said support, a pair ofterminals normally electrically connected by said fuse unit andsupported from said support, said fuse unit including a stationary fusetube, and a fuse link in fuse tube, one of said terminals having fuselink gripping and extracting means normally gripping said fuse link andyieldingly urged towards fuse link extracting position, said fuse linkgripping and extracting means releasing said fuse link after said fuselink has been extracted.

4.. A fuse construction comprising a support, a fuse unit mounted in asubstantially horizontal plane spaced from said support, a pair ofterminals normally electrically connected by said fuse unit supportedfrom said support, said fuse unit including a stationary fuse tube, anda fuse link in said fuse tube, one of said terminals hav ing fuse linkgripping and extracting means normally gripping said fuse link andyieldingly urged towards fuse link extracting position, said fuse unitbeing detachably related to said support.

5. A fuse construction comprising a support, a pair of terminalssupported from said support, a fuse unit including a fuse tube having anopen end and a fuse link therein and projecting from the open end ofsaid fuse tube, one of said terminals mechanically directly supportingsaid fuse tube, and a fuse link gripping and extracting means inchanically supported from the other of terminals and engaging said fuselink for extracting said fuse link, said fse link gripping andextracting means being free of connection with said fuse tube.

6. A fuse construction comprising a support, a pair of tcrlv .alssupported from said support, a fuse unit incuding a fuse tube and a fuselink therein, one of said terminals mechanically supporting said fusetube, and a fuse link gripping and extracting means mechanicallysupported roan the other of said terminals and engaging said fuse linkfor extracting said fuse link, said fuse link gripping and extractingmeans being free of connection with said fuse tube, said fuse linkgripping and extracting means releasing said fuse link after said fuselink gripping and extracting means has operated to extract any remainingportion of the fuse link after said fuse link blown.

'7. A fuse construction comprising a support, a pair of terminalssupported from said support, a fuse um't including a fuse tube and afuse link therein, one of said terminals mechanically supporting saidfuse tube, and a fuse link gripping and extracting means mechanicallysupported from the other of said terminals and engaging said fuse linkfor extracting said fuse link, said fuse link gripping and extractingmeans being free of connection with said fuse tube, said fuse linkgripping and extracting means including means for temporarily grippingsaid fuse lmk and a horizontally movable spring urged lever forextracting any remaining portion of said fuse link when said fuse linkhas blown.

8. A fuse construction comprising a support, a pair of terminalssupported from said support, a horizontally mounted. fuse tube, a fuselink within said fuse tube, supporting means for detachably supportingsaid fuse tube from one of said terminals, and fuse link extractingmeans mechanically distinct and separate from said fuse tube carried bythe other of said terminals, said fuse link extracting means being freeof connection with said fuse tube.

9. A fuse construction comprising a support, a pair of laterally spacedterminals projecting up" wardly from said support, an expulsion fusetube having at least one open end, means for supporting said expulsionfuse tube from one of said terminals, a fuse link carried within saidfuse tube and projecting from the open end thereof, and fuse linkgripping and extracting means carried by the other of said terminals andincluding a pivotally mounted spring urged fuse link extracting lever,a. portion of the gripping means being carried by said lever.

10. A fuse construction comprising a support, a pair of terminalssupported from said support, a fuse tube pivotally supported from one ofsaid terminals, fuse link receiving means carried by the other of saidterminals, a fuse link extending through said fuse tube and to said fuselink receiving means, and means urging said fuse tube for rotation in ahorizontal plane, said fuse link normally directly restraining rotationof said fuse tube.

11. A fuse construction comprising a support, a pair of terminalssupported from said support, a fuse tube pivotally supported from one ofsaid terminals, fuse link receiving means carried by the other of saidterminals, a fuse link extending through said fuse tube and to said fuselink receiving means, and spring means binding against said fuse linkand urging said fuse tube for rotation in a horizontal plane, rotationof said fuse tube being normally directly restrained by said fuse link.

12. A fuse construction comprising a support, a pair of terminalssupported from said support, a fuse tube pivotally supported from one ofsaid terminals and mounted to swing in a horizontal plane, said fusetube having an open end normally located adjacent the other of saidterminals, a headed fuse link extending through said fuse tube and outof the open end thereof and attached to the other of said terminals andnormally directly res raining rotation of said fuse tube, and sprinmeans urging said fuse tube towards rotation in a horizontal plane, saidspring means bearing against the head of said fuse link.

13. A fuse construction comprising a support, a pair of laterally spacedterminals projecting upwardly from said support, one of said terminalshaving pivot means, a. fuse tube having a projecting portion providedwith a pivot pin detachably received by said pivot means, a spring forpreventing inadvertent detachment of said pivot pin from said pivotmeans, said fuse tube being adapted to swing in a horizontal plane andhaving an open end normally located adjacent the other of saidterminals, the other of said terminals having fuse link receiving means,a fuse link carried within said fuse tube and projecting outwardlythrough the open end thereof to said fuse link receiving means, andspring means urging said fuse tube towards horizontal swinging motion,said fuse tube being normally restrained against swinging motion by saidfuse link.

14:. A fuse construction comprising a support, a pair of terminalssupported from said support, one of said terminals havin a projecting,substantially rigid member provided with a recessed portion adapted toreceive a pivot pin and having a spring normally approximately closingthe pivot pin receiving portion, a fuse tube having a pivot pindetachably positioned within the pivot pin receiving portion and havingan open end normally located adjacent the other of said terminals, afuse link within said fuse tube projecting outwardly through the openend thereof and extending to and secured to said last mentionedterminal, and a spring urging said fuse tube towards horizontal swingingmotion, said fuse link normally restraining the swinging motion of saidfuse tube.

15. A fuse construction comprising a support, a pair of terminalssupported therefrom, one of said terminals having fuse link receivingmeans, a horizontally mounted fuse tube having a contact at one endprovided with an aperture therethrough and having its other end open andnormally located adjacent said fuse link receiving means, a headed fuselink extending through said fuse tube with the head of said fuse linklocated exteriorly of the contact of said fuse tube and having one endof said fuse link projecting from the open end of said fuse tube andclamped by said fuse link receiving means, the contact of said fuse tubehaving a laterally projecting arm provided with a pivot pin, the otherof said terminals having a substantially rigid member provided with arecessed portion detachably receiving the said pivot pin, a spring forsubstantially closing said recessed portion to prevent inadvertentdetachment of the pivot pin, and a second spring bearing against thehead of said fuse link and urging said fuse tube towards horizontalswinging motion.

16. A fuse construction comprising a support having a pair of upwardlyprojecting terminals constituting a first terminal and a secondterminal, a horizontal fuse tube mechanically supported from said firstterr inal, and having an open end, said fuse tube being mechanicallyheld in a horizontal position after the fuse link has blown, a fuse linknormally connecting said terminals and located within said fuse tube andprojecting from the open end of said fuse tube, fuse link receiving andclamping supported from said second terminal and mechanically separateand distinct from said fuse tube, and means for causing relativemovement between said fuse tube and said fuse link receiving andclamping means.

17. A fuse construction comprising a support, a pair of verticallyspaced terminals projecting upwardly from said support, an expulsionfuse tube having at least one open end, means for supporting saidexpulsion fuse tube from one of said terminals, a fuse link carriedwithin said fuse tube and projecting from the open end thereof, and fuselink gripping and extracting means carried by the other of saidterminals and including a pivotally mounted spring urged fuse linkextracting lever, a portion of the gripping means being carried by saidlever.

18. A fuse construction comprising a support, a pair of verticallyspaced terminals supported from said support, a fuse tube pivotallysupported from one of said terminals, a fuse link receiving meanscarried by the other of said terminals, a fuse link extending throughsaid fuse tube to said fuse link receiving means, and means urging saidfuse tube for rotation in a horizontal plane, said fuse link normallydirectly restraining rotation of said fuse tube.

\ ALWIN G. STEINMAYER.

